The present invention relates to a rolling stock ventilator and a ventilator control method, and more particularly to a rolling stock ventilator and control method suitable for railway rolling stock running through the tunnel, at the speed of above 200 km/h.
When railway rolling stock enters a tunnel at a high speed, a pressure inside the tunnel is greatly changed by essentially a piston action of the car, causing the car be subjected to a sudden pressure change. Thus, an imbalance occurs to the air feed volume of the ventilator air supply fan due to the change of the car external pressure, and causing the car internal pressure to be changed. This raises a problem of giving an unpleasant feeling to the passengers.
In, for example, Japanese Laid Open Patent Publication 1-168560 (1989) or U.S. Pat. No. 5,137,490 proposes to solve the above problems by providing a ventilator which increases the air feed volume by raising the air feed characteristics of an air supply fan and exhaust fan and an by reducing the flow path resistance of the flow path resistance changer, when the inclination or tendency of the car external pressure change and the absolute value of the car external pressure change have reached the value corresponding to the unpleasant feeling of the passenger.
The unpleasant feeling given to the passengers by car internal pressure change is determined by the absolute value of the car external pressure change and the inclination of the pressure change. Thus, even if the volume of the air is increased by raising the air feed characteristics of the air supply fan and exhaust fan are changed according to the degree of the car internal pressure change, and by decreasing the flow path resistance of the flow path resistance changer, the absolute value of the imbalance in the air feed volume of the air supply fan and exhaust fan is almost the same as before the air feed volume is increased. The car internal pressure changes independence upon the degree of imbalance between the supply air and exhaust air volumes. On the other hand, the range of the pressure change inside the tunnel when the car is running through the tunnel is increased in proportion to the second power of the speed of the railway rolling stock. If the car speed is increased, imbalance in the air feed volume of the air supply fan and exhaust fan is also increased, so that the car internal pressure change will exceed the tolerance, giving unpleasant feeling to the passengers.